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Effects of ultrasonic-assisted extraction on bioactive compounds,volatile flavors and antioxidant activities of vine tea water extracts
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作者 Xiao-Long Zhou Wei-Jin Jiang +2 位作者 Ji Yu Mao-Jun Yao Yun-Tong Li 《Traditional Medicine Research》 2025年第1期73-81,共9页
Background:Ampelopsis grossedentata,vine tea,which is the tea alternative beverages in China.In vine tea processing,a large amount of broken tea is produced,which has low commercial value.Methods:This study investigat... Background:Ampelopsis grossedentata,vine tea,which is the tea alternative beverages in China.In vine tea processing,a large amount of broken tea is produced,which has low commercial value.Methods:This study investigates the influence of different extraction methods(room temperature water extraction,boiling water extraction,ultrasonic-assisted room temperature water extraction,and ultrasonic-assisted boiling water extraction,referred to as room temperature water extraction(RE),boiling water extraction(BE),ultrasonic assistance at room temperature water extraction(URE),and ultrasonic assistance in boiling water extraction(UBE))on the yield,dihydromyricetin(DMY)content,free amino acid composition,volatile aroma components,and antioxidant properties of vine tea extracts.Results:A notable influence of extraction temperature on the yield of vine tea extracts(P<0.05),with BE yielding the highest at 43.13±0.26%,higher than that of RE(34.29±0.81%).Ultrasound-assisted extraction significantly increased the DMY content of the extracts(P<0.05),whereas DMY content in the RE extracts was 59.94±1.70%,that of URE reached 66.14±2.78%.Analysis revealed 17 amino acids,with L-serine and aspartic acid being the most abundant in the extracts,nevertheless ultrasound-assisted extraction reduced total free amino acid content.Gas chromatography-mass spectrometry analysis demonstrated an increase in the diversity and quantity of compounds in the vine tea water extracts obtained through ultrasonic-assisted extraction.Specifically,69 and 68 volatile compounds were found in URE and UBE extracts,which were higher than the number found in RE and BE extracts.In vitro,antioxidant activity assessments revealed varying antioxidant capacities among different extraction methods,with RE exhibiting the highest DPPH scavenging rate,URE leading in ABTS•+free radical scavenging,and BE demonstrating superior ferric ion reducing antioxidant activity.Conclusion:The findings suggest that extraction methods significantly influence the chemical composition and antioxidant properties of vine tea extracts.Ultrasonic-assisted extraction proved instrumental in elevating the DMY content in vine tea extracts,thereby enriching its flavor profile while maintaining its antioxidant properties. 展开更多
关键词 vine tea DIHYDROMYRICETIN ultrasonic-assisted extraction volatile aroma components
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Adenosine cyclic phosphate with ultrasonic-assisted pectinase extraction alleviated allergic reactions in RBL-2H3 through inhibiting the influx of intracellular Ca^(2+)
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作者 Qiao Bai Xiaoping Feng +5 位作者 Yu Wang Chunyu Wu Ye Liu Jiao Sun Tianli Yue Fangyu Long 《Food Science and Human Wellness》 SCIE CSCD 2023年第3期832-841,共10页
Jujube contains abundant cyclic adenosine monophosphate(cAMP)and the ultrasonic-assisted pectinase extraction(UAPE)conditions for obtaining the maximum cAMP yield from jujube were optimized.Orthogonal array design was... Jujube contains abundant cyclic adenosine monophosphate(cAMP)and the ultrasonic-assisted pectinase extraction(UAPE)conditions for obtaining the maximum cAMP yield from jujube were optimized.Orthogonal array design was applied to evaluate the effects of 4 variables by UAPE on cAMP yield.The results showed that the optimal cAMP yield(783.0μg/g)was derived at ratio of liquid to solid 5 mL/g,ratio of pectinase to raw material 1.5%,time 60 min and temperature 40℃.Moreover,the effect of cAMP on the anti-allergic function of action induced by immunoglobulin E(IgE)and its meschanism was investigated through establishing the sensitized cell model in rat basophilic leukemia(RBL-2 H3)cells using dinitrophenylated(DNP)-bovine serum albumin(BSA)-IgE.The results showed that cAMP interfered with sensitized cells,effectively inhibited the occurrence of basophil degranulation in dose dependence,and significantly reduced the activity ofβ-hexosamindase(β-hex),at the optimal concentration of 50μg/mL.The level of anti-inflammatory factor interleukin-10(IL-10)was promoted and the content of pro-inflammatory factor tumor necrosis factor-α(TNF-α)was suppressed by cAMP.In addition,influx of intracellular Ca^(2+) was repressed effectively.Our results demonstrate that jujube cAMP regulated the cytokine balance in the allergy pathway through blocking the influx of extracellular Ca^(2+),with the prevention of allergy symptoms. 展开更多
关键词 ultrasonic-assisted pectinase extraction Cyclic adenosine monophosphate Rat basophilic leukemia cells Ca^(2+)influx Allergy
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Automated Extraction for Water Bodies Using New Water Index from Landsat 8 OLI Images 被引量:3
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作者 Pu YAN Yue FANG +2 位作者 Jie CHEN Gang WANG Qingwei TANG 《Journal of Geodesy and Geoinformation Science》 CSCD 2023年第1期59-75,共17页
The extraction of water bodies is essential for monitoring water resources,ecosystem services and the hydrological cycle,so analyzing water bodies from remote sensing images is necessary.The water index is designed to... The extraction of water bodies is essential for monitoring water resources,ecosystem services and the hydrological cycle,so analyzing water bodies from remote sensing images is necessary.The water index is designed to highlight water bodies in remote sensing images.We employ a new water index and digital image processing technology to extract water bodies automatically and accurately from Landsat 8 OLI images.Firstly,we preprocess Landsat 8 OLI images with radiometric calibration and atmospheric correction.Subsequently,we apply KT transformation,LBV transformation,AWEI nsh,and HIS transformation to the preprocessed image to calculate a new water index.Then,we perform linear feature enhancement and improve the local adaptive threshold segmentation method to extract small water bodies accurately.Meanwhile,we employ morphological enhancement and improve the local adaptive threshold segmentation method to extract large water bodies.Finally,we combine small and large water bodies to get complete water bodies.Compared with other traditional methods,our method has apparent advantages in water extraction,particularly in the extraction of small water bodies. 展开更多
关键词 water bodies extraction Landsat 8 OLI images water index improved local adaptive threshold segmentation linear feature enhancement
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Effectiveness of groundwater extraction in Beijing since the ingauration of the first phase of the South-to-North Water Diversion Project, China
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作者 Yuan-yuan Gao Qing-yu Sun +1 位作者 Ai-xin Wen Yan-pei Cheng 《Journal of Groundwater Science and Engineering》 2023年第3期294-307,共14页
This study assess the effectiveness of groundwater pressure extraction in Beijing since the opening of the first phase of the South-to-North Water Diversion Project,using survey and evaluation methods.Firstly,an analy... This study assess the effectiveness of groundwater pressure extraction in Beijing since the opening of the first phase of the South-to-North Water Diversion Project,using survey and evaluation methods.Firstly,an analysis of water consumption structure and the usage of diverted river water in Beijing in recent years was conducted.Secondly,the volume of groundwater pressure extraction in Beijing after the 33 project's inauguration was examined,revealing a decrease from 1.96 billion m^(3) in 2014 to 1.35 billion m^(3) in 2020.The proportion of water supply reduced from 52.3%in 2014 to 33.3%in 2020,leading to an optimized water supply structure.By the end of 2020,groundwater pressure extraction in Beijing is estimated at 446 million m3,with a substantial reduction in over-exploitation of groundwater.Groundwater resources have been effectively replenished,and the strategic reserve capacity has been enhanced.Furthermore,this study evaluates the change in groundwater levels as an indicator of the effectiveness of pressure extraction.The declining trend of groundwater levels in Beijing has been effectively mitigated,and there has been a consistent rebound in groundwater levels over the past five years. 展开更多
关键词 Beijing City South-to-North water Diversion Groundwater Over-exploitation Groundwater Pressure extraction
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Optimization of Ultrasonic-Assisted Extraction Process of Polysaccharides from American Ginseng and Evaluation of Its Immunostimulating Activity 被引量:7
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作者 YANG Xiu-shi WANG Li-jun +2 位作者 DONG Chuan Edmund Man King Lui REN Gui-xing 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2014年第12期2807-2815,共9页
Ultrasonic-assisted extraction (UAE) of American ginseng polysaccharides (AGP) was investigated using response surface methodology. Three-factor-three-level Box-Behnken design was employed to optimize the ultrason... Ultrasonic-assisted extraction (UAE) of American ginseng polysaccharides (AGP) was investigated using response surface methodology. Three-factor-three-level Box-Behnken design was employed to optimize the ultrasonic power, extraction time and ratio of water to raw material to obtain a high AGP yield. The analysis of variance and response surface plots indicated that ultrasonic power was the most important factor affecting the extraction yield. The optimal conditions were ultrasonic power 400 W, extraction time 71 min, and ratio of water to raw material 33 mL g-1. Under these conditions, the yield of AGP was 8.09%, which was agreed closely to the predicted value. Gas chromatography (GC) analysis showed that AGP was composed of arabinose, rhamnose, galactose, glucose, and galacturonic acid. Fourier transform infrared spectra revealed the general characteristic absorption peaks of AGP. In addition, AGP exhibited good immunostimulating activities by up-regulating the production of nitric oxide and cytokines. Compared with hot water extraction, UAE required shorter extraction time and gave a higher extraction yield, without changing the structure and immunostimulating activity of AGP. The results indicated that UAE could be an effective and advisable technique for the large scale production of plant polysaccharides. 展开更多
关键词 ultrasonic-assisted extraction POLYSACCHARIDES American ginseng response surface methodology immunostimulating activity
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Antioxidant and hepatoprotective effects of Ajuga nipponensis extract by ultrasonic-assisted extraction 被引量:3
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作者 Chang-Wei Hsieh Wen-Ching Ko +3 位作者 Wai-Jane Ho Chao-Kai Chang Guo-Jhou Chen Jen-Chieh Tsai 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2016年第5期409-414,共6页
Objective: To investigate suitable condition for extraction of the active components from Ajuga nipponensis(A. nipponensis). Methods: Orthogonal experimental design was used to determine the optimal extraction paramet... Objective: To investigate suitable condition for extraction of the active components from Ajuga nipponensis(A. nipponensis). Methods: Orthogonal experimental design was used to determine the optimal extraction parameters for ecdysterones and flavonoids. Finally, the hepatoprotective abilities of A. nipponensis extracts were evaluated by CCl_4-induced animal models. Results:Maximum yields of flavonoids(7.87±0.10) mg/g and ecdysterones(0.73±0.02) mg/g could be obtained when the extraction time was 50 min, the extraction temperature was 60 ℃, and the ratio of sample to 70%(v/v) ethanol was 1:20(w/w). The antioxidant property of A. nipponensis was correlated to the concentration of its extracts. At 5 mg/m L, A. nipponensisextract scavenged 84.8% of DPPH radical and had absorbance values of 2.43±0.04 reducing power. Upon CCl_4-induced liver injury, glutamic oxaloacetic transaminase and glutamic pyruvic transaminase decreased significantly after the mice were treated with A. nipponensis. Histological researches also explained that A. nipponensis reduced the extent of liver lesions induced by CCl_4. Conclusions: A. nipponensis exhibited potent antioxidant activity in chemical experimental models and hepatoprotective effect against CCl_4-induced liver damage. 展开更多
关键词 Ajuga nipponensis ultrasonic-assisted extraction ORTHOGONAL test ANTIOXIDANT HEPATOPROTECTION
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Optimization of Response Surface of Ultrasonic-assisted Extraction of Rizhao Black Tea 被引量:1
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作者 TANG Yu-huan LIANG Qing +2 位作者 ZOU Jia-jia DING Xin DING Li-xiao 《Chinese Food Science》 2012年第3期35-38,共4页
[ Objectivel The aim was to determine the optimal technology for ultrasonic-assisted extraction of black tea was determined. [ Methed] Taking Black Tea as materials, the Box-Behnken response surface design method of t... [ Objectivel The aim was to determine the optimal technology for ultrasonic-assisted extraction of black tea was determined. [ Methed] Taking Black Tea as materials, the Box-Behnken response surface design method of tea polyphenols ultrasonic-assisted extraction process optimi- zation was applied. The regression optimization model of the ethanol volume fraction, ultrasonic time, and ultrasonic temperature, ethyl acetate extract stalling time and tea polyphenols was established. [ Result] The influence of four factors on the black tea polyphenol solvents affecting size was as follows: ultrasonic time 〉 ethanol volume fraction 〉 stalling extraction time 〉 ultrasound temperature. The best extraction process was ultrasonic time 80 min, volume fraction of 88.99% ethanol, extraction time 89.97 min, ultrasonic temperature of 80℃. At the optimized technical parameters, the black tea phenolic extraction yield can be as high as 73.50%. [ Conclusion] The study provided theoretical basis for the development of tea leaves and black tea. 展开更多
关键词 Rizhao black tea ultrasonic-assisted extraction extraction yield Response surface China
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Mathematical modeling for of arctigenin from acidultrasonic-assisted extractionhydrolyzed FructusArctii
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作者 Dai Lin Zhang Yong +2 位作者 Hu Chi Qian Hongliang Wang Zhixiang 《Journal of Southeast University(English Edition)》 EI CAS 2017年第3期362-369,共8页
A mathematical model based on Fick's first lawwas established to describe the process of ultrasonic-assisted extraction of arctigenin from acid hydrolyzed FructusArctii.Acid hydrolization with hydrochloric acid pr... A mathematical model based on Fick's first lawwas established to describe the process of ultrasonic-assisted extraction of arctigenin from acid hydrolyzed FructusArctii.Acid hydrolization with hydrochloric acid promotes the conversion of arctiin to arctigenin in the arctiin-rich active pharmaceutical ingredient, and the hydrolyzed products were further examined to investigate the process setup. By considering the mechanism of the extraction process and experimental data, the effects of parameters including solven to solid ratio, particle size of hydrolyzed samples, ethano volume fraction, ultrasound power, extraction temperature and extraction time on concentration of arctigenin were analyzed in detail. The model was suitable for simulating the process of ultrasonic-assisted extraction of arctigenin. The simulation results of the model agree well with experimental data with the deviation below13%, indicating that the mathematical mode can provide valuable guidance for the extraction of arctigenin from acid hydrolyzed FructusArctii. 展开更多
关键词 FructusArctii acid hydrolysis ultrasonic-assisted extraction ARCTIGENIN mathematical model
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Study on Processing of Clear Banana Juice Using Hot Water Extraction Method 被引量:2
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作者 郑欣 余元善 +4 位作者 吴继军 徐玉娟 肖更生 黄婉华 温靖 《Agricultural Science & Technology》 CAS 2014年第11期2003-2005,2044,共4页
In this study, the effects of hot water temperature on clarity, total soluble solids, polyphenol oxidase (PPO) and color of banana juice during hot water ex-traction were discussed based on the theory in which heat ... In this study, the effects of hot water temperature on clarity, total soluble solids, polyphenol oxidase (PPO) and color of banana juice during hot water ex-traction were discussed based on the theory in which heat treatment might induce the pectin and protein in banana pulp to form insoluble products. The results showed the hot water temperature had a significant effect on the formation of insol-uble polymers in banana pulp from pectin and protein. In 75 ℃ water, the pectin and protein in banana pulp were most inclined to form insoluble products. Under this condition, the clarity of banana juice was also highest. The light transmittance at 660 nm was close to 90%. In the banana juice, extracted by 75 ℃ water, the pectin and protein contents were lowest, and they were lower than 7.3 mg/100 ml and 12.9 mg/100 ml respectively. The 75 ℃ water could not inactivate completely the pectin in banana pulp due to its high heat resistance, Therefore, 0.05% L-cys-teine or ascorbic acid needed to be added into banana pulp to inhibit the browning of juice induced by residual PPO. 展开更多
关键词 Clear banana juice Hot water extraction Polyphenol oxidase Pectin Protein
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Economy, environmental assessment and energy conservation for separation of isopropanol/diisopropyl ether/water multi-azeotropes via extractive distillation coupled pervaporation process 被引量:2
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作者 Qinggang Xu Yasen Dai +6 位作者 Qing Zhao Zhengrun Chen Peizhe Cui Zhaoyou Zhu Yinglong Wang Jun Gao Yixin Ma 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第2期353-363,共11页
This wok proposed the extraction distillation coupled pervaporation(ED+PV) technology process using two different solvents to separate isopropanol(IPA) and diisopropyl ether(DIPE) from DIPE/IPA/H_(2)O ternary heteroge... This wok proposed the extraction distillation coupled pervaporation(ED+PV) technology process using two different solvents to separate isopropanol(IPA) and diisopropyl ether(DIPE) from DIPE/IPA/H_(2)O ternary heterogeneous azeotropes in industrial wastewater from the synthesis of isopropanol in this study.Based on strict design specifications, simulation and sequential iteration methods are used for process design and optimization. Compared to the ethylene glycol(EG)-EG+H_(2)O process and the 1,3-propanediol(PDO)-IPA+H_(2)O process, the total annual cost(TAC) of the EG-IPA+H_(2)O process decreased by 20.76% and 7.86%(PDO). Compared to the EG-EG+H_(2)O process, the TAC of the PDO-IPA+H_(2)O process reduced 14%, but the global warming potential(GWP) and human toxicity of the PDO-IPA+H_(2)O process increased 11.3% and 4.07% respectively. Compared to the PDO-IPA+H_(2)O process, the EG-IPA+H_(2)O process saves 7.86%(TAC), 9.78%(GWP) and 9.85%(human toxicity). The ED+PV process with EG is superior to PDO in factors of TAC, energy consumption, human toxicity and environment. The EG-IPA+H_(2)O process changed the separation order of the products of the multi-azeotropic system, reduced the cost and energy conservation of the system, and enhanced the environmental protection evaluation of the process, is the best process through life cycle assessment for analyzing the economy, energy conservation, environmental assessment and human toxicity, designing cleaner products, controlling waste discharge, and promoting the chemical purification industry. This work provides a new process design and optimized separation ideas, will have a good guiding significance for the research and application separation of multi-azeotropic mixture with mixed solvents in organic wastewater from the cleaner chemical production, has been up to standard wastewater discharge process, and realized the development goal of carbon peak and carbon neutrality in the sustainable development of chemical clean industry. 展开更多
关键词 Life cycle assessment extractive distillation coupled pervaporation Isopropanol/diisopropyl ether/water azeotropes Thermodynamic efficiency Human toxicity
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Allelopathic Effects of Water Extracts of Sweet Potato (Ipomoea batatas) on Seed Germination of Ageratum conyzoides 被引量:1
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作者 Shuangshuang Zhang Wenlei Cheng +2 位作者 Ye Chen Mingxing Jiang Genshen Yin 《Journal of Agricultural Chemistry and Environment》 CAS 2023年第2期124-133,共10页
Sustainable weed management strategies are essential to reduce chemical and labor inputs. This study aimed to evaluate the effect of water extracts from sweet potato [Ipomoea batatas (L.) Lamarck] on seed germination ... Sustainable weed management strategies are essential to reduce chemical and labor inputs. This study aimed to evaluate the effect of water extracts from sweet potato [Ipomoea batatas (L.) Lamarck] on seed germination of Ageratum conyzoides L. under controlled conditions. The aqueous was produced from plant parts i.e., roots, stems, and leaves of sweet potato at concentrations of 0.025, 0.050, 0.075, and 0.100 g·mL<sup>-1</sup>. The results showed that the plant parts of sweet potato all contained allelopathic substances, which showed high-concentration inhibition and low-concentration promotion of seed germination of A. conyzoides. When the aqueous extract concentrations were 0.050, 0.075, and 0.100 g·mL<sup>-1</sup>, the germination of A. conyzoides seeds was inhibited, while the germination was promoted at a concentration of 0.025 g·mL<sup>-1</sup>. This shows that when the planting density of sweet potato is large, it can form an obvious prevention and control effect on A. conyzoides, and thus improve herbicide resistance management. 展开更多
关键词 Sweet Potato geratum conyzoides water extracts Allelopathic Effect
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Extracting water body data based on SDWI and threshold segmentation:A case study in permafrost area surrounding Salt Lake in Hoh Xil,Qinghai-Tibet Plateau,China 被引量:1
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作者 QingSong Du GuoYu Li +4 位作者 Dun Chen ShunShun Qi Yu Zhou Fei Wang YaPeng Cao 《Research in Cold and Arid Regions》 CSCD 2023年第4期202-209,共8页
There are a large number of lakes,rivers,and other natural water bodies distributed in the permafrost area of the Qinghai-Tibet Plateau(QTP).The changes in water bodies will affect the distribution of water resources ... There are a large number of lakes,rivers,and other natural water bodies distributed in the permafrost area of the Qinghai-Tibet Plateau(QTP).The changes in water bodies will affect the distribution of water resources in sur-rounding areas and downstream areas,resulting in environmental impact and bringing potential flood disasters,which will induce more serious issues and problems in alpine and high-altitude areas with a fragile habitat(such as the QTP in China).Generally,effective,reasonable,and scientific monitoring of large-scale water bodies can not only document the changes in water bodies intuitively,but also provide important theoretical reference for subsequent environmental impact prediction,and disaster prevention and mitigation in due course of time.The large-scale water extraction technology derived from the optical remote sensing(RS)image is seriously affected by clouds,bringing about large differences among the extracted water result products.Synthetic aperture radar(SAR)RS technology has the unique advantage characteristics of all-weather,all-day,strong penetration,and not being affected by clouds,which is hopeful in extracting water body data,especially for days with cloudy weather.The data extraction of large-scale water bodies based on SAR images can effectively avoid the errors caused by clouds that become prevalent at present.In this paper,the Hoh Xil Salt Lake on the QTP and its surrounding five lakes are taken as the research objects.The 2-scene Sentinel-1 SAR image data covering the whole area on 22 August 2022 was used to verify the feasibility of extracting water body data in permafrost zones.Furthermore,on 22 August 2022,the wealth here was cloudy,which made the optical RS images,e.g.,Sentinel-2 images full of clouds.The results show that:using the Sentinel-1 image and threshold segmentation method to extract water body data is efficient and effective with excellent results in permafrost areas.Concretely,the Sentinel-1 dual-polarized water index(SDWI),calculated by combining dual vertical–vertical(VV)polarized and verti-cal–horizontal(VH)polarized data is a useful index for water extraction and the result is better than each of the VV or VH polarized images. 展开更多
关键词 Permafrost region water body extraction Salt Lake in Hoh Xil Qinghai-Tibet Plateau Sentinel-1 Ecological environment impact Disaster prevention and mitigation
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Determination of Ultratrace Amounts of Copper(Ⅱ) in Water Samples by Electrothermal Atomic Absorption Spectrometry After Cloud Point Extraction 被引量:10
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作者 CHEN Jian-guo CHEN neng-wu +2 位作者 CHEN Shao-hong LIN Li ZHONG Ying-ying 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2007年第2期143-147,共5页
A novel approach was developed for the determination of ultratrace amounts of copper in water samples by using electrothermal atomic absorption spectrometry (ETAAS) after cloud point extraction ( CPE ). 1-( 2-Pyr... A novel approach was developed for the determination of ultratrace amounts of copper in water samples by using electrothermal atomic absorption spectrometry (ETAAS) after cloud point extraction ( CPE ). 1-( 2-Pyridylazo ) -2- naphthol was used as the chelating reagent and Triton X-114 as the mieellar-forming surfactant. CPE was conducted in a pH 8. 0 medium at 40 ℃ for 10 rain. After the separation of the phases by contrifugafion, the surfactant-rieh phase was diluted with 1 mL of a methanol solution of 0. 1 mol/L HNO3. Then 20μL of the diluted surfactant-rieh phase was injected into the graphite furnace for atomization in the absence of any matrix modifier. Various experimental conditions that affect the extraction and atomization processes were optimized. A detection limit of 5 ng/L was obtained after preconeentration. The linear dynamic range of the copper mass concentration was found to be 0-2.0 ng/mL, and the relative standard deviation was found to be less than 3. 1% for a sample containing 1.0 ng/mL Cu ( Ⅱ ). This developed method was successfully applied to the determination of uhratraee amounts of Cu in drinking water, tap water, and seawater samples. 展开更多
关键词 Cloud point extraction Preconeentration Electrothermal atomic absorption spectrometry Copper( Ⅱ) water analysis
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Determination of volatile organic compounds in river water by solid phase extraction and gas chromatography 被引量:4
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作者 M.A.Mottaleb M.Z.Abedin M.S.Islam 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2004年第3期497-501,共5页
A simple, rapid, and reproducible method is described employing solid phase extraction(SPE) using dichloromethane followed by gas chromatography(GC) with flame ionization detection(FID) for determination of volatile ... A simple, rapid, and reproducible method is described employing solid phase extraction(SPE) using dichloromethane followed by gas chromatography(GC) with flame ionization detection(FID) for determination of volatile organic compound(VOC) from the Buriganga River water of Bangladesh. The method was applied to detect the benzene, toluene, ethylbenzene, xylene and cumene(BTEXC) in the sample collected from the surface or 15 cm depth of water. Two hundred ml of n hexane pretreated and filtered water samples were applied directly to a C 18 SPE column. BTEXC were extracted with dichloromethane and average concentrations were obtained as 0 104 to 0 372 μg/ml. The highest concentration of benzene was found as 0 372 μg/ml with a relative standard deviation(RSD) of 6 2%, and cumene was not detected. Factors influencing SPE e.g., adsorbent types, sample load volume, eluting solvent, headspace and temperatures, were investigated. A cartridge containing a C 18 adsorbent and using dichloromethane gave better performance for extraction of BTEXC from water. Average recoveries exceeding 90% could be achieved for cumene at 4℃ with a 2 7% RSD. 展开更多
关键词 solid phase extraction river water environmental analysis VOC recoveries
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Proposed Models for Subcritical Water Extraction of Essential Oils 被引量:9
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作者 M.Khajenoori A.Haghighi Asl F.Hormozi 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2009年第3期359-365,共7页
Mechanisms that control the extraction rate of essential oil from Zataria multiflora Boiss. (Z. multiflora) with subcritical water (SW) were studied. The extraction curves at different solvent flow rates were used to ... Mechanisms that control the extraction rate of essential oil from Zataria multiflora Boiss. (Z. multiflora) with subcritical water (SW) were studied. The extraction curves at different solvent flow rates were used to deter-mine whether the extractions were limited primarily by the near equilibrium partitioning of the analyte between the matrix and solvent (i.e. partitioning thermodynamics) or by the rates of analyte desorption from the matrix (i.e. ki-netics). Four simple models have been applied to describe the extraction profiles obtained with SW: (1) a model based solely on the thermodynamic distribution coefficient KD, which assumes that analyte desorption from the ma-trix is rapid compared to elution; (2) one-site kinetic model, which assumes that the extraction rate is limited by the analyte desorption rate from the matrix, and is not limited by the thermodynamic (KD) partitioning that occurs dur-ing elution; (3) two-site kinetic model and (4) external mass transfer resistance model. For SW extraction, the thermodynamic elution of analytes from the matrix was the prevailing mechanism as evidenced by the fact that ex-traction rates increased proportionally with the SW flow rate. This was also confirmed by the fact that simple re-moval calculations based on determined KD (for major essential oil compounds) gave good fits to experimental data for flow rates from 1 to 4 ml·min-1. The results suggested that the overall extraction mechanism was influenced by solute partitioning equilibrium with external mass transfer through liquid film. 展开更多
关键词 essential oils Zataria multiflora Boiss. subcrltlcal water extraction mechanisn
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Recovery of Caprolactam from Waste Water in Caprolactam Production Using Pulsed-sieve-plate Extraction Column 被引量:5
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作者 刘建青 谢方友 +1 位作者 何潮洪 朱明乔 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2002年第3期371-373,共3页
Recovery of caprolactam from waste water of caprolactam production factory was investigated using benzene as solvent in a small-scale pulsed-sieve-plate column. First, liquid-liquid equilibrium (LLE) data were measure... Recovery of caprolactam from waste water of caprolactam production factory was investigated using benzene as solvent in a small-scale pulsed-sieve-plate column. First, liquid-liquid equilibrium (LLE) data were measured, including water-caprolactam-benzene system at low caprolactam concentrations, and waste water-benzene system. Then, the operating regions and mass transfer of the pulsed-sieve-plate column were measured. Finally, the overall apparent heights of a transfer unit based on continuous phase are correlated in terms of the column operation variables. 展开更多
关键词 pulsed-sieve-plate column extraction e-caprolactam waste water
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Cloud-point extraction and preconcentration of bisphenol A from water samples 被引量:2
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作者 谭志坚 李芬芳 《Journal of Central South University》 SCIE EI CAS 2012年第8期2136-2141,共6页
A novel cloud-point extraction (CPE) was successfully used in preconcentration of biphenol A (BPA) from aqueous solutions. Majority of BPA is extracted into the surfactant-rich phase. The parameters affecting the ... A novel cloud-point extraction (CPE) was successfully used in preconcentration of biphenol A (BPA) from aqueous solutions. Majority of BPA is extracted into the surfactant-rich phase. The parameters affecting the CPE such as concentration of surfactant and electrolyte, equilibration temperature and time and pH of sample solution were investigated. The samples were analyzed by high-performance liquid chromatography with ultraviolet detection. Under the optimized conditions, preconcentration of 10 mL sample gives a preconcentration factor of 11. The limit of detection (LOD) and limit of quantification (LOQ) are 0.1 μg/L and 0.33 μg/L, respectively. The linear range of the proposed method is 0.2-20 μg/L with correlation coefficients greater than 0.998 7 and the spiking recove6es are 97.96%-100.42%. The interference factor was tested and the extraction mechanism was also investigated. Thus, the developed CPE has proven to be an efficient, green, rapid and inexpensive approach for extraction and preconcentration of BPA from water samples. 展开更多
关键词 biphenol A cloud-point extraction extraction mechanism high-performance liquid chromatography water samples
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Salting-Out Assisted Liquid-Liquid Extraction Combined with HPLC for Quantitative Extraction of Trace Multiclass Pesticide Residues from Environmental Waters 被引量:2
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作者 Yosef Alemayehu Teshome Tolcha Negussie Megersa 《American Journal of Analytical Chemistry》 2017年第7期433-448,共16页
In this study, salting-out assisted liquid-liquid extraction combined with high performance liquid chromatography diode array detector (SALLE-HPLC-DAD) method was developed and validated for simultaneous analysis of c... In this study, salting-out assisted liquid-liquid extraction combined with high performance liquid chromatography diode array detector (SALLE-HPLC-DAD) method was developed and validated for simultaneous analysis of carbaryl, atrazine, propazine, chlorothalonil, dimethametryn and terbutryn in environmental water samples. Parameters affecting the extraction efficiency such as type and volume of extraction solvent, sample volume, salt type and amount, centrifugation speed and time, and sample pH were optimized. Under the optimum extraction conditions the method was linear over the range of 10 - 100 μg/L (carbaryl), 8 - 100 μg/L (atarzine), 7 - 100 μg/L (propazine) and 9 - 100 μg/L (chlorothalonil, terbutryn and dimethametryn) with correlation coefficients (R2) between 0.99 and 0.999. Limits of detection and quantification ranged from 2.0 to 2.8 μg/L and 6.7 to 9.5 μg/L, respectively. The extraction recoveries obtained for ground, lake and river waters were in a range of 75.5% to 106.6%, with the intra-day and inter-day relative standard deviation lower than 3.4% for all the target analytes. All of the target analytes were not detected in these samples. Therefore, the proposed SALLE-HPLC-DAD method is simple, rapid, cheap and environmentally friendly for the determination of the aforementioned herbicides, insecticide and fungicide residues in environmental water samples. 展开更多
关键词 Environmental waters High Performance Liquid Chromatography SALTING-OUT ASSISTED LIQUID-LIQUID extraction Southern Ethiopia TRACE MULTICLASS Pesticide Residues
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Water Extract of Rice False Smut Balls Activates Nrf2/HO-1 and Apoptosis Pathways,Causing Liver Injury
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作者 ZHANG Guomei LI Han +4 位作者 LIU Shanshan ZHOU Xuming LU Mingyang TANG Liang SUN Lihua 《Rice science》 SCIE CSCD 2023年第5期473-485,I0025-I0028,共17页
Ustiloxins are vital cyclopeptide mycotoxins originally isolated from rice false smut balls that form in rice spikelets infected by the fungal pathogen Ustilaginoidea virens.The toxicity of the water extract of rice f... Ustiloxins are vital cyclopeptide mycotoxins originally isolated from rice false smut balls that form in rice spikelets infected by the fungal pathogen Ustilaginoidea virens.The toxicity of the water extract of rice false smut balls(RBWE) remains to be investigated.Studies have shown that RBWE may be toxic to animals,but toxicological evidence is still lacking.In this study,we found that the IC50 values of RBWE to BNL CL.2 cells at 24 and 48 h were 40.02 and 30.11 μg/m L,respectively,with positive correlations with dose toxicity and time toxicity.After treatment with RBWE,the number of BNL CL.2 cells decreased significantly,and the morphology of BNL CL.2 cells showed atrophy and wall detachment.RBWE induced DNA presynthesis phase arrest of BNL CL.2 cells,increased the proportion of apoptotic cells and inhibited cell proliferation.RBWE up-regulated reactive oxygen species(ROS) levels and lowered mitochondrial membrane potentials.Additionally,Western blot and q RT-PCR results suggested that RBWE exerted the above effects by promoting the Nrf2/HO-1 and caspase-induced apoptosis pathways in vitro and in vivo.The contents of alanine aminotransferase,aspartate aminotransferase,alkaline phosphatase,and total bile acids in the serum of mice from Institute of Cancer were significantly up-regulated by RBWE.At the same time,RBWE can lead to increases in ROS and malondialdehyde contents,decreases in contents of oxidized glutathione,glutathione and reduced glutathione,as well as decrease in catalase and superoxide dismutase activities in mouse liver tissues,demonstrating that oxidative stress occurred in mice.Moreover,liver damage was further detected by haematoxylin-eosin staining and electron microscopy to verify the damage to the mice caused by RBWE.In general,RBWE may cause hepatotoxicity in vivo and in vitro via the apoptosis pathway,which provides a reference for hepatotoxicity and its mechanism of action. 展开更多
关键词 water extract rice false smut ball ustiloxin liver injury Nrf2/HO-1 pathway apoptosis pathway
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Simultaneous Determination of Bisphenols and Alkylphenols in Water by Solid Phase Extraction and Ultra Performance Liquid Chromatography-tandem Mass Spectrometry 被引量:4
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作者 SHAN Xiao Mei SHEN Deng Hui +2 位作者 WANG Bing Shuang LU Bei Bei HUANG Fa Yuan 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2014年第6期471-474,共4页
To establish an analytical method for determination of four bisphenols (BPA, BPB, BPF, and BPS) and two alkylphenols (4-n-OP, 4-n-NP) in water by ultra performance liquid chromatography- tandem mass spectrometry ... To establish an analytical method for determination of four bisphenols (BPA, BPB, BPF, and BPS) and two alkylphenols (4-n-OP, 4-n-NP) in water by ultra performance liquid chromatography- tandem mass spectrometry (UPLC/MS/MS). The water samples were extracted and condensed with solid-phase extraction (SPE) using C18 cartridges and eluted by acetonitrile. Separation was carried out with Acquity BEH C8 column and detection were performed by UPLC/MS/MS. Quantification was calculated by using the internal standard BPA-d16 and 4-n-NP-d8. The linear correlation coefficients of these compounds in the range of 1.0-100.0μg/L were all over 0.999. The minimum detectable concentrations were 0.75-1.0 ng/L, and the recoveries ranged from 87.0% to 106.9%. 展开更多
关键词 UPLC BPA Simultaneous Determination of Bisphenols and Alkylphenols in water by Solid Phase extraction and Ultra Performance Liquid Chromatography-tandem Mass Spectrometry MASS
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